int Datagram_GetMessage (qsocket_t *sock)
{
unsigned int length;
unsigned int flags;
int ret = 0;
struct qsockaddr readaddr;
unsigned int sequence;
unsigned int count;
if (!sock->canSend)
if ((net_time - sock->lastSendTime) > 1.0)
ReSendMessage (sock);
while(1)
{
length = sfunc.Read (sock->socket, (byte *)&packetBuffer, NET_DATAGRAMSIZE, &readaddr);
// if ((rand() & 255) > 220)
// continue;
if (length == 0)
break;
// >>> FIX: For Nintendo Wii using devkitPPC / libogc
// sfunc.Read might return error values other than -1. Changing:
//if (length == -1)
if (length < 0)
// <<< FIX
{
Con_Printf("Read error\n");
return -1;
}
if (sfunc.AddrCompare(&readaddr, &sock->addr) != 0)
{
#ifdef DEBUG
Con_DPrintf("Forged packet received\n");
Con_DPrintf("Expected: %s\n", StrAddr (&sock->addr));
Con_DPrintf("Received: %s\n", StrAddr (&readaddr));
#endif
continue;
}
if (length < NET_HEADERSIZE)
{
shortPacketCount++;
continue;
}
length = BigLong(packetBuffer.length);
flags = length & (~NETFLAG_LENGTH_MASK);
length &= NETFLAG_LENGTH_MASK;
if (flags & NETFLAG_CTL)
continue;
sequence = BigLong(packetBuffer.sequence);
packetsReceived++;
if (flags & NETFLAG_UNRELIABLE)
{
if (sequence < sock->unreliableReceiveSequence)
{
Con_DPrintf("Got a stale datagram\n");
ret = 0;
break;
}
if (sequence != sock->unreliableReceiveSequence)
{
count = sequence - sock->unreliableReceiveSequence;
droppedDatagrams += count;
Con_DPrintf("Dropped %u datagram(s)\n", count);
}
sock->unreliableReceiveSequence = sequence + 1;
length -= NET_HEADERSIZE;
SZ_Clear (&net_message);
SZ_Write (&net_message, packetBuffer.data, length);
ret = 2;
break;
}
if (flags & NETFLAG_ACK)
{
if (sequence != (sock->sendSequence - 1))
{
Con_DPrintf("Stale ACK received\n");
continue;
}
if (sequence == sock->ackSequence)
{
sock->ackSequence++;
if (sock->ackSequence != sock->sendSequence)
Con_DPrintf("ack sequencing error\n");
}
else
{
Con_DPrintf("Duplicate ACK received\n");
continue;
}
sock->sendMessageLength -= MAX_DATAGRAM;
if (sock->sendMessageLength > 0)
{
Q_memcpy(sock->sendMessage, sock->sendMessage+MAX_DATAGRAM, sock->sendMessageLength);
sock->sendNext = true;
}
else
{
sock->sendMessageLength = 0;
sock->canSend = true;
}
continue;
}
if (flags & NETFLAG_DATA)
{
packetBuffer.length = BigLong(NET_HEADERSIZE | NETFLAG_ACK);
packetBuffer.sequence = BigLong(sequence);
sfunc.Write (sock->socket, (byte *)&packetBuffer, NET_HEADERSIZE, &readaddr);
if (sequence != sock->receiveSequence)
{
receivedDuplicateCount++;
continue;
}
sock->receiveSequence++;
length -= NET_HEADERSIZE;
if (flags & NETFLAG_EOM)
{
SZ_Clear(&net_message);
SZ_Write(&net_message, sock->receiveMessage, sock->receiveMessageLength);
SZ_Write(&net_message, packetBuffer.data, length);
sock->receiveMessageLength = 0;
ret = 1;
break;
}
Q_memcpy(sock->receiveMessage + sock->receiveMessageLength, packetBuffer.data, length);
sock->receiveMessageLength += length;
continue;
}
}
if (sock->sendNext)
SendMessageNext (sock);
return ret;
}
int Datagram_GetMessage (qsocket_t *sock)
{
unsigned int length;
unsigned int flags;
int ret = 0;
struct qsockaddr readaddr;
unsigned int sequence;
unsigned int count;
if (!sock->canSend)
if ((net_time - sock->lastSendTime) > 1.0)
ReSendMessage (sock);
while(1)
{
length = sock->landriver->Read(sock->socket, (byte *)&packetBuffer, NET_DATAGRAMSIZE, &readaddr);
/*
// for testing packet loss effects
if ((rand() & 255) > 220)
continue;
*/
if (length == 0)
break;
if ((int)length == -1)
{
Con_Printf("Read error\n");
return -1;
}
// added !sock->net_wait (NAT fix)
if (!sock->net_wait && sock->landriver->AddrCompare(&readaddr, &sock->addr) != 0)
{
#ifdef DEBUG
Con_DPrintf("Forged packet received\n");
Con_DPrintf("Expected: %s\n", StrAddr (&sock->addr));
Con_DPrintf("Received: %s\n", StrAddr (&readaddr));
#endif
continue;
}
if (length < NET_HEADERSIZE)
{
shortPacketCount++;
continue;
}
length = BigLong(packetBuffer.length);
flags = length & (~NETFLAG_LENGTH_MASK);
length &= NETFLAG_LENGTH_MASK;
// ProQuake extra protection
if (length > NET_DATAGRAMSIZE)
{
Con_Warning ("Datagram_GetMessage: excessive datagram length (%d, max = %d)\n", length, NET_DATAGRAMSIZE);
return -1;
}
if (flags & NETFLAG_CTL)
continue;
sequence = BigLong(packetBuffer.sequence);
packetsReceived++;
// NAT fix
if (sock->net_wait)
{
sock->addr = readaddr;
strcpy(sock->address, sock->landriver->AddrToString(&readaddr));
sock->net_wait = false;
}
if (flags & NETFLAG_UNRELIABLE)
{
if (sequence < sock->unreliableReceiveSequence)
{
Con_DPrintf("Got a stale datagram\n");
ret = 0;
break;
}
if (sequence != sock->unreliableReceiveSequence)
{
count = sequence - sock->unreliableReceiveSequence;
droppedDatagrams += count;
Con_DPrintf("Dropped %u datagram(s)\n", count);
}
sock->unreliableReceiveSequence = sequence + 1;
length -= NET_HEADERSIZE;
SZ_Clear (net_message->message);
SZ_Write (net_message->message, packetBuffer.data, length);
ret = 2;
break;
}
if (flags & NETFLAG_ACK)
{
if (sequence != (sock->sendSequence - 1))
{
Con_DPrintf("Stale ACK received\n");
continue;
}
if (sequence == sock->ackSequence)
{
sock->ackSequence++;
if (sock->ackSequence != sock->sendSequence)
Con_DPrintf("ack sequencing error\n");
}
else
{
Con_DPrintf("Duplicate ACK received\n");
continue;
}
sock->sendMessageLength -= MAX_DATAGRAM;
if (sock->sendMessageLength > 0)
{
// FIXME: was memcpy
memmove(sock->sendMessage, sock->sendMessage + MAX_DATAGRAM, sock->sendMessageLength);
sock->sendNext = true;
}
else
{
sock->sendMessageLength = 0;
sock->canSend = true;
}
continue;
}
if (flags & NETFLAG_DATA)
{
packetBuffer.length = BigLong(NET_HEADERSIZE | NETFLAG_ACK);
packetBuffer.sequence = BigLong(sequence);
sock->landriver->Write(sock->socket, (byte *)&packetBuffer, NET_HEADERSIZE, &readaddr);
if (sequence != sock->receiveSequence)
{
receivedDuplicateCount++;
continue;
}
sock->receiveSequence++;
length -= NET_HEADERSIZE;
if (flags & NETFLAG_EOM)
{
SZ_Clear(net_message->message);
SZ_Write(net_message->message, sock->receiveMessage, sock->receiveMessageLength);
SZ_Write(net_message->message, packetBuffer.data, length);
sock->receiveMessageLength = 0;
ret = 1;
break;
}
memcpy(sock->receiveMessage + sock->receiveMessageLength, packetBuffer.data, length);
sock->receiveMessageLength += length;
continue;
}
}
if (sock->sendNext)
SendMessageNext (sock);
return ret;
}
